A London bakery recently experienced the worst-case scenario of offering a Groupon for a small business, and it cost the owner thousands.

Need a Cake bakery owner Rachel Brown decided to put up a 75 percent discount on a dozen cupcakes on the site, which dropped the price down to $10 from $40.

Apparently, people really love getting cupcakes cheap, because she was rushed by throngs of customers in a cupcake frenzy.

A total of 8,500 people signed up, and her crew of eight had to make 102,000 cupcakes to meet the orders.

Brown lost $3 per batch because she had to hire 25 extra workers to help, and she ended up losing $20,000 because of it, which is a ton for a small biz. It wiped out her profits for the year, reports the Daily Mail.

"Without doubt, it was my worst ever business decision," she told the BBC. "We had thousands of orders pouring in that really we hadn't expected to have. A much larger company would have difficulty coping."

Well, it looks like most small businesses think so. An overwhelming majority of 70 percent hate Groupon, if the latest survey from iContact is to be believed.

As for Brown and her bakery, the experience may have cost her 20 grand, but what about all the exposure she's getting for her store? Great, right? It doesn't hurt, but it probably wasn't worth the cost.

Small businesses like this bakery thrive on relationships with their local customers, not crowds of outsiders coming in to snatch up a free lunch.

Getting new customers is great, but in this case, the bakery rewarded the wrong customers. Those 8,500 people that rushed for the Groupon probably won't be coming back to pay for the same cupcakes at quadruple the price.

Only those the store has nurtured relationships with for a long time (in Brown's case, 25 years), should be the ones rewarded. They're the ones that keep coming back for more.